Material handling equipment



Mm'ch 30, 1965 w. A. HERPICH ETAL 3,175,712

MATERIAL HANDLING EQUIPMENT 4 Sheets-Sheet 1 Filed June 6, 1961 INVENTOR5 ATTORNEYS 4 Sheets-Sheet 2 W. A. HERPICH ETAL MATERIAL HANDLINGEQUIPMENT March 30, 1965 Filed June 6, 1961 March 30, 1965 w. A. HERPICHETAL 3,175,712

MATERIAL HANDLING EQUIPMENT 4 Sheets-Sheet 5 Filed June 6, 1961INVENTORS ATTORNEYE' arch 1965 w. A. HERPICH ETAL 3,175,712

MATERIAL HANDLING EQUIPMENT 4 Sheets-Sheet 4 Filed June 6. 1961 BY M 0 MM, 74,1 4:-

ATTORNEY 3,175,712 MATEL HANDLING EQUIPMENT William A. I-Ierpich,Gallon, Ohio, and Neil F. Wender and Glenmore G. Garrett, Knoxville,Tenn, assignors to Dempster Brothers, inc, Knoxville, Tenn, acorporation of Tennessee Filed .lune 6, 1961, Ser. No. 115,177 5 Claims.(Cl. 214-303) This invention relates to improvements in materialhandling equipment of the character involving containers andvehicle-mounted container hoisting apparatus. This equipment frequentlyis used in collecting and transporting loose material such as refuse,for example.

A satisfactory way of handling loose material is to provide containersof suitable size into which the material may be deposited. In thecollection of refuse, for example, several suitable containers may beplaced at convenient locations and emptied from time to time as they arefilled. These containers are of relatively large size and the handlingof these containers requires a power actuated mechanism.

One type of mechanism used to service such containers is generallyreferred to as a front end loader or front end loading equipment. Thiscontainer handling equipment employs a pair of lifting arms which arepivotally connected to the vehicle and extend to the front of thevehicle where a connection may be established between the lifting armsand a container. The vehicle is provided with a body of such a characterthat the contents of the container may be emptied into the body uponproper actuation of the hoisting equipment.

One front end loader device is shown, for example, in Patent No.2,900,096 issued August 18, 1959, and includes, in addition to a pair oflifting arms, a front torque tube extending across the vehicle forconnecting the lifting arms, and a pair of fork arms mounted on thetorque tube and serving to establish a detachable connection between thecontainer and the lifting arms.

In this front end loading equipment the fork arms extend along theoutside of the container and fit into pockets or sleeve assemblies atthe ends of the container. Actuation of the lifting arms and the forkarms by suitable power devices is effected to lift the container, fromthe ground or other supporting surface, over the cab of the vehicle to aposition above the body of the vehicle so that the contents of thecontainer may be dumped through a hopper opening into the body. Theempty container may then be swung back to the ground in front of thevehicle.

When containers are emptied by front end loading equipment, it is notnecessary to transport the containers themselves to a distant locationfor dumping. A vehicle equipped with this type of front end loader, andwith a suitable body, is driven from point to point where variouscontainers are located. One after another, the full containers may beemptied into the body of the vehicle and, once the body is full, thevehicle can be driven to the dumping area and the contents emptied fromthe body. In this manner, it is not necessary to remove the containersfrom the filling location, and the number of trips which the vehiclemust make to a dumping location can be minimized.

In equipping a vehicle with a front end loader, it is desirous that thehoisting apparatus be actuated by power devices under the control of theoperator located within the cab of the vehicle, or at a suitableposition outside the cab. A convenient Way of actuating the hoistingapparatus is to provide fluid under pressure for actuating suitablecylinder and piston assemblies. It is desirous that the operation of thehoisting equipment be as simple I aten ice as possible and that thecontainer dumping operation be completed rapidly.

The body of the vehicle customarily is provided with a door or cover forthe hopper opening. When the hoisting apparatus is actuated to dump thecontents of a container into the body, it is necessary, of course, thatthe cover be open. In providing simple and rapidly operating containerhandling apparatus, it is necessary that the hopper cover be actuated toits open and close positions in proper sequence in connection with theactuation of the lifting arms which hoist the container into positionabove the hopper. It is desirous also, that the actuation of the hoppercover be automatic, that is, that it be operated without the need forthe operator to give his attention to opening or closing the hoppercover.

Accordingly, one object of this invention is to provide vehicle mountedcontainer handling apparatus for dumping the contents of a container.

Another object of this invention is to provide a hydrau lic system foractuating and controlling vehicle-mounted container hoisting equipment.

Another object of this invention is to provide a hydraulically actuatedhopper cover for the body of a vehicle.

Another object of this invention is to provide a system forautomatically opening and closing a hopper cover in sequence with theactuation of container handling apparatus.

These objects may be accomplished according to one embodiment of thisinvention by providing, in connection with vehicle-mounted front endloading equipment, a hydraulically actuated and controlled systemwherein the hoisting apparatus is operated manually by an operator, anda hopper cover is opened and closed automatically in response tomovement of the hoisting apparatus.

The hoisting apparatus includes a pair of lifting arms pivotally mountedto the vehicle through a rear torque tube. Fork arms are provided at thefront of the lifting arms for establishing a connection with a containerwhich is to be hoisted above the body of the vehicle. The body isprovided with a hopper opening through which material from the containermay be dumped into the body. The hopper cover is pivotally mountedadjacent the hopper opening and swung between open and close positionsby a cylinder and piston assembly. Additional cylinder and pistonassemblies are provided for actuating the hoisting apparatus as well asa packer device within the vehicle body.

In the control system, fluid is supplied under pressure by a pump to abank of manually actuated valves which control the flow of fluid to thecontainer hoisting apparatus and the packer device. There is included inthe control system a valve which is positioned adjacent the hoistingapparatus to be actuated thereby when the hoisting apparatus has moved acertain distance during a container dumping operation. Another valve islocated adjacent the rear of the hopper cover to be actuated therebywhen the cover is opened. These two valves aid in controlling theopening and closing of the hopper cover.

This embodiment of the invention is illustrated in the accompanyingdrawings, in which:

FIG. 1 is a side elevation view of a vehicle equipped with front endloading equipment, and showing in full lines and broken lines thehoisting equipment and the container in various positions;

FIG. 2 is an enlarged plan view of a hopper cover for the body of thevehicle;

FIG. 3 is a side elevation view corresponding with FIG. 2;

FIG. 4 is an enlarged fragmentary elevation view showing therelationship of one of the valves of a control system in associationwith the rear torque tube of the hoisting apparatus;

FIG. is a fragmentary front elevation view of part of the structureshown in FIG. 4;

FIGS. 6 and 7 are diagrammatic views showing a manner of actuating avalve of the control system by a cam on the rear torque tube; and

FIG. 8 is a diagrammatic view of the control system of the front endloading equipment.

In FIG. 1 there is illustrated a container It which is of relativelylarge size and which is capable of receiving loose material such astrash, or the like. The container 10 normally rests upon the ground, orother supporting surface, at a convenient location, and is provided withsuitable openings at its top portion through which material may bedeposited. The container 10 must be emptied from time to time as itbecomes full, and this may be accomplished by inverting the container soas to dump the contents through an opening in the top wall.

A suitable vehicle is selected for receiving the hoisting apparatuswhich may handle the container 10. The vehicle is indicated in FIG. 1 bythe reference numeral 12. The vehicle 12 has a chassis 13 and is selfpropelled under the control of an operator located within a cab 14.

A body 16 is provided on the vehicle chassis 13 behind the cab 14 andmay be of any suitable type for receiving the particular material to behandled. For example, the body 16 may be built up of plates andstrengthened as necessary by a series of reinforcing ribs 17. Theinterior of the body 16 provides ample room for receiving the materialto be transported; however, it is often desirable that the interior ofthe body 16 be equipped with a packer mechanism for compressing materialwithin the body. The packer mechanism may include a slidable packer headactuated by a hydraulic cylinder for compressing the material.

The top portion of the front of the body 16 is provided with a hopperopening 18 through which material may be dumped into the body 16. Sideplates 19 extend along each side of the hopper 18 and cooperate with anangled front plate 20 (FIGS. 2 and 3) for guiding the material throughthe hopper opening 18 as the material is dumped from the container 10. Adoor 21 is provided at the rear of the body 16 so that the material maybe emptied from the body 16 under the assistance of the packermechanism. The door 21 normally is latched closed.

The hopper opening 18 in the body 16 is equipped with a cover 22 whichmay be built up of plates 2 and strengthened as necessary by alongitudinal central rib 26, a lateral rib 28, and suitable crossbracing 30. Framing 31 around the sides of the cover 22 suppliesadditional rigidity and ensures a tight fit between the cover and theplates 19 and 20. The cover 22 is hinged or otherwise pivotallyconnected at 32 to the top of the body 16, rearward of the opening 18,so as to be movable between a closed position (FIGS. 2 and 3) or anopened position (FIG. 1).

The opening and closing of the cover 22 is effected by actuation of apower device 36, which may be, for example, a conventional hydraulicallyactuated cylinder and piston assembly, including a cylinder 33 and apiston rod 40. The cylinder 38 is pivotally mounted at 42 to a pair ofbrackets 46 which extend upwardly from a plate 48 fixed to the top ofthe body 16. The free end of the piston rod 40 is pivotally connected at50 to a pair of brackets 52 which extend upwardly from the juncture ofthe central rib 26 and the lateral rib 28 of the cover 22.

The power device 36 is preferably of the double acting type whichpermits fluid under pressure to be introduced at either end of thecylinder 33 so as to move the piston rod 40 inwardly or outwardly of thecylinder 38. Thus, the cylinder device 36 may be retracted to swing thecover 22 upwardly about the pivotal connection 32 from its closedposition to its opened position, and the power de vice 36 may beextended to swing the cover downwardly from its opened position to itsclosed position.

The front end loading equipment or hoisting apparatus used in connectionwith the vehicle 12 is indicated in FIG. 1 by reference numeral 60, andincludes a pair of lifting arms 62 spaced apart a distance correspondingsubstantially with the width of the cab 14. The lifting arms 62 may beof gooseneck shape or inverted U-Shape, for example, so as to extendover the top and downwardly in front and back of the cab 14, asillustrated in FIG. 1.

At the back of the cab 14 the lower end of the lifting arms 62 are fixedon a horizontally extending rear torque tube or rod 64 which extendssubstantially from one side of t e vehicle 12 to the other. The torquetube 64 is journaled in bearing blocks 66 (FIGS. 4 and 5) which arefixed to the vehicle chassis 13. In this manner, the lifting arms 62 arepivotally mounted to the vehicle 12 through the rear torque tube 64 andthe bearing blocks 66.

A pair of lever arms 70 are attached to each opposite end of the torquetube 64 and extend downwardly therefrom. A power device 72, for example,a conventional hydraulically actuated cylinder and piston assembly,including a cylinder 74 and piston rod 76, is provided at each side ofthe vehicle 12 adjacent each pair of lever arms 76. The rear of eachcylinder 74 is pivotally connected at 78 to brackets 80 fixed to thechassis 13. The free end of each piston rod 76 is pivotally connected at82 to the free end of adjacent lever arms 71).

At the front of the vehicle 12, the lifting arms 62 are connected by ahorizontally extending front torque tube or rod 94 which is journaled inbearing boxes secured to the forward ends of lifting arms 62. On eachoutside end of the torque tube 94 there is fixed a pair of lever arms96. A power device 93, for example, a conventional hydraulicallyactuated cylinder and piston assembly, including cylinder and piston rod102, is mounted on each of the lifting arms 62 by means of a bracket104- so that the power device 98 extends along the corresponding arm 62.The free end of each piston rod 102 is connected at 106 with the freeend of corresponding lever arms 96. A pair of fork arms 110 are rigidlymounted on opposit ends of the torque tube 94 adjacent the lifting arms62.

On opposite end walls of the container 10 there is securely attached asleeve assembly 112 which receives one of the fork arms 11% of thelifting mechanism 60. When the container 10 and the vehicle 12 are inthe positions i1- lustrated in FIG. 1, the fork arms 110 may be insertedinto or removed from the sleeve assemblies 112 in order to establish adetachable connection between the hoisting apparatus 60 and thecontainer It).

The hoisting apparatus 60 may be operated as follows in order to dumpthe contents of the container 10 into the body 16 through the hopperopening 18. The power devices 100 may be actuated under the force ofhydraulic pressure to rotate the lever arms 96 which in turn rotate thetorque tube 94 so as to properly align the fork arms 110 for entranceinto the sleeves 112. The lifting arms 62 may be pivoted about the axisof the rear torque tube 64 by operation of the power devices 72. Inorder to establish a connection between the lifting mechanism 6t) andthe container 10 while it is on the ground or other supporting surfacein front of the vehicle 12, the vehicle is maneuvered into properposition, and the power devices 72 and 98 are operated so that the forkarms 110 will enter the sleeves 112.

The power devices 72 may be operated further to swing the lifting arms62 upwardly so that the container 19 is hoisted over the cab 14 and intodumping position at the top and front of the body 16 above the hopperopening 18. During the raising of the container lit, the fork arms 110may be actuated by the power devices 98 to rotate slightly in acounterclockwise direction with reference to FIG. 1 so that thecontainer 11) may be kept slightly tilted toward the vehicle butsubstantially upright. Once the container 10 is above the hopper opening18, the fork arms 119 may be actuated to rotate in a clockwise directionfar enough so that the container 10 is inverted to dump the contentsfrom the top of the container 11), through the hopper opening 18 andinto the body 16. This latter position of the lifting apparatus 60 andcontainer is illustrated in broken lines in FIG. 1.

After the contents of the container 10 are dumped in this manner, thepower devices 98 may be actuated to rotate the fork arms 110 so that thecontainer 10 will be returned to a generally upright position. Thelifting arms 62 then may be lowered by proper actuation of the powerdevices 72 to swing the container 10 to the front of the vehicle 12.Lifting apparatus of similar nature is illustrated and described indetail in Patent No. 2,900,096, issued August 18, 1959.

Normally, the cover 22 is closed over the hopper opening 18; however,when the lifting apparatus 60 is actuated to swing the container 10intodumping position, the cover 22 automatically swings to its open positionillustrated in FIG. 1. Then, when the hoisting apparatus 60 is actuatedto lower the container 10, the cover 22 is actuated to swing to itsclosed position. A hydraulic system for actuating the hoisting apparatus69 and the cover 22 is illustrated diagrammatically in FIG. 8. Thehoisting apparatus 60 is under the control of the operator while he islocated within the cab 14, but the opening and closing of the cover 22is effected automatically without the attention of the operator. Thehydraulic system includes a storage tank or reservoir 120 which may bemounted on the chassis 13 of the vehicle 12 and which contains fluidneeded for use throughout the system. Suitable fluid conduits or linesare illustrated diagrammatically in FIG. 8 and such lines may beemployed as necessary in connection with the several members of thecontrol system. All lines, however, for the sake of clarity, have notbeen illustrated throughout the drawings.

Fluid from the reservoir 120 is supplied through a line 104 containing amanually operated valve 106 to a pump 108. This pump 108 may be of anysuitable type neces sary for providing the needed fluid under pressureand may be driven by the power take off mechanism of the vehicle 12.

Fluid under pressure from the pump 108 is supplied to a relief valve111. Excess fluid may return from the relief valve 111 through a line112 and a line 114 back to the reservoir 120. Normally, however, fluidwill pass from the relief valve 111 through a line 116 to a normallyopen cam operated valve 120, through a line 122, into a line 124containing a check valve 126, through a line 128, and into a bank ofcontrol valves 130. The bank of control valves 130 may be located withinthe cab 14 in convenient reach of the operator. If desired, a similarbank of control valves may be located outside the vehicle 12, but thisarrangement is not illustrated in FIG. 8.

The fluid under pressure will flow as previously described when thelifting arms 62 of the hoisting apparatus 60 are in the positionillustrated in FIG. 1, for example, as when a container 10 is about tobe hoisted to dumping position. The bank of control valves 130 containsseparate valves 132, 134 and 136 for controlling the flow of fluid tothe power devices 72 which raise and lower the lifting arms 62, to thepower devices 98 which rotate the fork arms 110, and to a cylinderdevice 140 which actuates a packer mechanism within the body 16.

When fluid flows under pressure into the valve bank 130, the valve 132may be moved to one position to allow fluid to pass into a line 142 andthen into the rear of the cylinders 74 to raise the lifting arms 62, or,the valve 132 may be moved to another position to allow fluid to passinto a line 144 and then into the forward end of the cylinders 74 tolower the lifting arms 62.

The valve 134 may be moved to one position to allow fluid under pressureto pass through a line 146 and into the rear of cylinders 100 to rotatethe fork arms 110 in a clockwise direction with reference to FIG. 1, or,the valve 134 may be moved to another position to allow fluid to passthrough a line 148 into the forward end of the cylinders to rotate thefork arms in a counterclockwise direction.

The valve 136 may be moved to one position to allow fluid to passthrough a line 150 and into the cylinder 149 to extend the packermechanism toward the rear of the vehicle to pack the contents within thebody 116, or, the valve 136 may be moved to another position to allowfluid to pass through a line 152 and into the cylinder to retract thepacker mechanism towards the front of the body 16 so that material maybe dumped into the body.

Fluid under pressure passing into the cylinder 140 through either theline 150 or the line 152 may overflow into either line 156 or 158 andthen through a return valve 160. This fluid, instead of returning to thereservoir 120, may be returned to the cylinder 140 in order to keep thecylinder 140 full of fluid at all times. Excess fluid not needed to keepthe cylinder full will be returned to the reservoir 120. A manuallyactuated valve 162 is provided in the line 150 for additional control ofthe flow of fluid to the cylinder 140.

The cam operated valve 120 is normally opened under the force of aspring within the valve to allow fluid to pass therethrough when thelifting arms 62 are in a lowered position. The valve 120 is actuated bya cam device to control the opening of the cover 22. The cam device 170is located on the rear torque tube 64, as illustrated in FIGS. 4-7.

The valve 120 is mounted on the body 16 above the rear torque tube 64between the lever arms 70 by a bracket 166. The cam member 170, whichfor example may be a curved plate member, is mounted between the pair oflever arms 70 in the manner illustrated in FIGS. 6 and 7. The cam 170 ispositioned about the torque tube 64 so as to rotate with the torque tube64.

The valve 120 has an actuating arm 172 equipped with a cam follower 174which may engage the cam 170. The cam 170 and the cam follower 174 arepositioned so that when the lifting arms 62 are lowered, the camfollower 174 is not engaged by the cam 170 (FIG. 7), and the valve 120is open to allow fluid pressure to flow freely to the valve bank 130.

After the lifting cams 62 have been raised a short distance at thebeginning of a dumping operation of the container 10, the torque tube 64will be rotated and in turn the cam 170 will be moved into position toengage the cam follower 174 of the valve 120 (FIG. 6). The cam 1'70 andthe cam follower 174 are positioned so that the cam 170 pushes in on thearm 172 of the valve 120 after the lifting arms 62 have been raised to aposition wherein the container 10 has completed only part of itsmovement to its dumping position, for example, to a position above thecab 14. The free flow of fluid under pressure through the valve 120 willbe stopped. Fluid under pressure, instead of flowing into the line 122,will be backed up and flow through a line into the forward end of thecylinder 38 of the power device 36.

This flow of fluid under pressure into the forward part of the cylinder38 retracts the piston rod 40 into the cylinder causing the cover 22 toswing to its opened position. t this time, fluid will not flow throughthe line 122 to the valve bank 130. Movement of the lifting arms 62 willstop, even though the valve 132 is open. Similarly, the fork arms 110may not be rotated even though the valve 134 is open. Under thiscondition the check valve 126 in the line 124 serves an importantfunction by preventing a backward flow of fluid out of the cylinders 74and 100 of the power devices 72 and 98. Thus, the lifting arms 62 areheld in their partially raised position and the fork arms 110 are heldmotionless while fluid flows from the pump 108 through the line 180 intothe forward end of the cylinder 38 to open the cover 22. During the timethat the valve 120 is closed under action of the cam 170, excess fluidnot flowing through the line 180 is returned to the reservoir 120through a line 192 and the line 114.

A shut off valve 186 is mounted on top of the body 16 adjacent the powerdevice 36 and immediately to the rear of the cover 22. This valve isprovided with an arm 1-53 which is in position to be contacted and movedinwardly of the valve 136 when the cover 22 is moved upwardly to itscompletely opened position. Normally, the arm 183 extends outwardly fromthe valve 186 and the valve is closed under the force of a spring withinthe valve.

As fluid under pressure continues to flow through the line 18% into theforward end of the cylinder 38, the cover 22 continues its upwardswinging movement until it strikes the arm 188 of the valve 186 therebyopening the valve 186. This opening of the valve 186 allows fluid toflow from the line 180 through a line 192, into the line 128, and theninto the valve bank 130. With fluid pressure now being supplied from thepump through the valves 11% and 188 and to the valve bank 130, the powerdevices 72 are again supplied with fluid under pressure to continuemoving the lifting arms 62 upwardly. The valves 132 and 134 may beactuated as necessary to swing the container to dumping position abovethe hopper opening 18. The cover 22 will be opened and the hopperopening 18 will be free to receive the material from the container 10.The valve 134 may be controlled to actuate the power devices 98 torotate the fork arms 110, so that the container 10 will be inverted asillustrated by broken lines in FIG. 1. In addition, fluid can besupplied through line 150 or 152 under control of the valve 136 to thepacker cylinder 140.

After the power devices 98 have been actuated to invert the container 10to dump the contents through the hopper opening 13 into the body 16, thesystemmay be actuated as follows in order to lower the lifting arms 62to return the container 10 to the ground in front of the vehicle 16,during which time the cover will close automatically.

While fluid is flowing from the pump 108 through the lines 180, 192 and123 to the valve bank 13f), the cylinder devices 98 can be actuatedunder control of the valve 134 to return the container 10 to a generallyupright position. Then the power devices 72 can be actuated to beginswinging the lifting arms downwardly After the lifting arms 62 havetraveled a predetermined distance downwardly, for example to a positionwhere the container 11) is over the cab 14, the cam 170 and cam follower174 will break contact, and the spring within the valve 120 will thenmove the valve to its opened position. With the valve 129 open again,fiuid is free to flow from the pump 103 through the valve 120, throughlines 122, 124 and 128 to the valve bank 130.

Fluid under pressure in the line 122 divides and part flows into theline 124 and part flows into a line 1% to the rear of the cylinder 38.Fluid under pressure in the rear of the cylinder 38 extends the pistonrod 49 causing the cover 22 to swing downwardly to its closed position.At this time, the lifting arms 62 have moved downwardly far enough tomove the container 10 away from the hopper opening 18 and out of the wayof the cover 22.

After the cover 22 has moved downwardly slightly, the arm 188 breakscontact with the cover 22 and the valve 186 is closed under the actionof the spring within the valve thereby shutting off the flow of fluidthrough the line 192. All of the fluid flowing through the line 180 willgo into the front of the cylinder 38. As fluid under pressure continuesto flow through the line 196 into the rear portion of the cylinder 38,the cover 22 will continue to close. The rear face of the piston in thecylinder 33 has an effective area larger than the effective area of thefront face thereby allowing fluid within the rear of the cylinder 38 tooverbalance the fluid pressure within the front so as to force thepiston rod 40 to its extended position. This keeps the cover 22 closedtightly.

With fluid flowing freely from the pump 108 through the valve 120 to thevalve bank 130, the manually ac- 8 tuated valves 132, 134 and 136 may becontrolled as desired to actuate the cylinder devices 72, 98 or 140. Thefork arms and the lifting arms 62 can be actuated to disconnect thelifting apparatus 61) from the container 10 and the packer mechanism maybe actuated to compress the material within the body 16. The vehicle 12is ready to be driven to a new location where another full containersuch as the container 10 is located, and another dumping operation maybe carried out in the same man ner. The vehicle 12 may continue fromcontainer to container until the body 16 is full. As necessary, thepacker cylinder 141! may be actuated to compress the material within thecontainer 16. After the body 16 is full, the vehicle may be driven to adumping location where the rear door 21 may be unlatched, and thematerial dumped from the body 16 under the assistance of the packermechanism by actuating the packer cylinder 140.

The control system gives the operator complete control over the dumpingoperation in a simple and effective manner. The operator may direct hisfull attention to the movement of the lifting arms and fork arms becauseof the automatic control of hopper cover. The timing of the opening andclosing of the cover with respect to the position of the container isdetermined safely and positively due to the positional relationship ofthe cam and cam operated valve 120.

While the invention has been illustrated and described in one preferredembodiment, it is recognized that other variations and changes may bemade therein without departing from the invention as set forth in theclaims.

We claim:

l. in container handling equipment; including a body having an opening,arms for moving a container over the opening and away from the opening,control means for moving the arms, and a cover for the opening; a systemfor opening and closing the cover including a source of fluid pressure,cylinder means for moving the cover, means for conducting a flow offluid from the source to the control means, means for changing the flowof fluid from the control means to the cylinder means to open the coverbefore the arms move the container over the opening, and second meansfor conducting a flow of fluid from the source to the control meansafter the cover is open.

2. In container handling equipment; including a body having an opening,arms for moving a container over the opening and away from the opening,control means .for moving the arms, and a cover for the opening; asystem for opening and closing the cover including a source of fluidpressure, cylinder means for moving the cover, means for conducting aflow of fluid from the source to the control means, means for changingthe flow of fluid from the control means to the cylinder means to openthe cover before the arms move the container over the opening, secondmeans for conducting a flow of fluid from the source to the controlmeans after the cover is open, and means for conducting a flow of fluidfrom the source to the cylinder means to close the cover after the armsmove the container away from the opening.

3. In a control system for a front end loader including a body mountedon a vehicle, said body having an opening in the top thereof; liftingarms pivotally mounted to the vehicle for vertical swinging movement;fork arms operatively mounted on the lifting arms for verticalrotational movement with respect thereto, the lifting arms and fork armscooperating to lift a container above the opening and dump the contentsthereof into the body; and a cover for the opening; the combination offluid pressure means for controlling movement of the lifting arms andthe fork arms; a cylinder assembly for moving the cover to open andclose positions with respect to the opening in the body; a reservoir forfluid; a first, normally open valve; a pump for supplying fluid underpressure through the first valve to said fluid pressure means; a second.normally closed valve; means for closing the first valve in response toupward movement of the lifting arms to cause fluid to flow to thecylinder for opening the cover, the second valve positioned to be openedby the cover after the cover is open to allow fluid to flow from thepump through the second valve to said fluid pressure means; and meansfor opening the first valve in response to d-ownward movement of thelifting arms to allow fluid to flow through the first valve to thecylinder assembly for closing the cover.

4. In a control system for a front end loader including a body mountedon a vehicle, said body having an opening in the top thereof; liftingarms pivotally mounted to the vehicle for vertical swinging movement;fork arms operatively mounted on the lifting arms for verticalrotational movement with respect thereto, the lifting arms and fork armscooperating to lift a container above the opening and dump the contentsthereof into the body; and a cover for the opening; the combination of afirst cylinder assembly for swinging the lifting arms; a second cylinderassembly for rotating the fork arms; a third cylinder assembly formoving the cover to open and close positions with respect to the openingin the body; a valve bank including separate valves for controlling theflow of fluid to the first and second cylinder assemblies; a reservoirfor fluid; a first, normally open valve; a pump for supplying fluidunder pressure through the first valve to the valve bank; a second,normally closed valve; and means for closing the first valve afterpredetermined upward swinging of the lifting arms to cause fluid to flowfrom the pump to one end of the third cylinder assembly for opening thecover, the second valve positioned to be opened by the cover after thecover is open to allow fluid to flow from the pump through the secondvalve to the valve bank, said means opening the first valve afterpredetermined downward swinging of the lifting arms to allow fluid toflow through the first valve to the other end of the third cylinderassembly for closing the cover.

5. In a control system for a front end loader including a body mountedon a vehicle, said body having an opening in the top thereof; liftingarms pivotally mounted to the vehicle for vertical swinging movement;fork arms operatively mounted on the lifting arms for verticalrotational movement with respect thereto, the lifting arms and fork armscooperating to lift a container above the opening and dump the contentsthereof into the body; and a cover for the opening; the combination or"a first cylinder assembly for swinging the lifting arms; a secondcylinder assembly for rotating the fork arms; a third cylinder assemblyfor moving the cover to open and close position with respect to theopening in the body; a valve bank including separate valves forcontrolling the flow of fluid to the first and second cylinderassemblies; a reservoir for fluid; a first, normally open valve; a checkvalve; a pump for supplying fluid under pressure through the firstvalve, through the check valve, to the valve bank; a second, normallyclosed valve; and a cam movable with the lifting arms for closing thefirst valve after predetermined upward swinging of the lifting arms tocause fluid to flow from the pump to one end of the third cylinderassembly for opening the cover, the second valve positioned to be openedby the cover after the cover is open to allow fluid to flow from thepump through the second valve to the valve bank, the cam opening thefirst valve after predetermined downward swinging of the lifting arms toallow fluid to flow through the first valve to the other end of thethird cylinder assembly for closing the cover.

References Cited by the Examiner UNITED STATES PATENTS 1,851,502 3/32Ferris et a1. 2l4-16.l2 X 1,922,851 8/33 Howard 214-303 X 1,953,579 4/34Zeuthen 214-302 X 2,101,067 12/37 Howard 214-303 X 2,170,932 8/39 Venema214-303 X 2,826,318 3/58 Beasley 214-302 X 2,873,872 2/59 Zoller 214-3032,877,910 3/59 Nelson 214-302 2,951,600 9/60 Dempster et a1 214-302 XFOREIGN PATENTS 1,229,167 9/60 France.

HUGO O. SCHULZ, Primary Examiner. MORRIS TEMIN, Examiner.

1. IN CONTAINER HANDLING EQUIPMENT; INCLUDING A BODY HAVING AN OPENING,ARMS FOR MOVING A CONTAINER OVER THE OPENING AND AWAY FROM THE OPENING,CONTROL MEANS FOR MOVING THE ARMS, AND A COVER FOR THE OPENING; A SYSTEMFOR OPENING AND CLOSING THE COVER INCLUDING A SOURCE OF FLUID PRESSURE,CYLINDER MEANS FOR MOVING THE COVER, MEANS FOR CONDUCTING A FLOW OFFLUID FROM THE SOURCE TO THE CONTROL MEANS, MEANS FOR CHANGING THE FLOWOF FLUID FROM THE CONTROL MEANS TO THE CYLINDER MEANS TO OPEN THE